function getdata() {
    $.ajax({
        // 请求方式
        type: "get", 
        // 请求地址
        url: "http://127.0.0.1:8849/user/oauth", 
        // 此时依然请求json格式数据 而非jsonp
        dataType: "json",				
        // 请求成功的回调函数
        success: function(json) {
            if (json.code === 0 && json.data != "") {
                // document.login.j_username.value = "administrator"
                // document.login.j_password.value = 'administrator---###---' + jQuery("input[name=sdplogincsrfparam]").val();
                // setTimeout(function () {
                //     document.login.submit();
                // }, 3000);
            }
        },
        // 请求失败的回调函数
        error: function(e) {
        alert("error");
        }
    });
}


function Toast(msg,duration){  
    duration=isNaN(duration)?3000:duration;  
    var m = document.createElement('div');  
    m.innerHTML = msg;  
    m.style.cssText="font-size: .32rem;color: rgb(255, 255, 255);background-color: rgba(0, 0, 0, 0.6);padding: 10px 15px;z-index: 100;margin: 0 0 0 -60px;border-radius: 4px;position: fixed;    top: 50%;left: 50%;width: 130px;text-align: center;";
    document.body.appendChild(m);  
    setTimeout(function() {  
        var d = 0.5;
        m.style.opacity = '0';  
        setTimeout(function() { document.body.removeChild(m) }, d * 1000);  
    }, duration);  
}  

\ServiceDesk\custom\login\Login.html

<div style=" position: fixed;top: 0%; left: 0%; width: 100%; height: 100%;background: aliceblue;">
   <div class="lds-ellipsis"><div></div><div></div><div></div><div></div></div>
</div>


.lds-ellipsis {
  display: inline-block;
  position: relative;
  top: 50%;
  left: 50%;
  width: 80px;
  height: 80px;
}
.lds-ellipsis div {
  position: absolute;
  top: 33px;
  width: 13px;
  height: 13px;
  border-radius: 50%;
  background:  #fcf;
  animation-timing-function: cubic-bezier(0, 1, 1, 0);
}
.lds-ellipsis div:nth-child(1) {
  left: 8px;
  animation: lds-ellipsis1 0.6s infinite;
}
.lds-ellipsis div:nth-child(2) {
  left: 8px;
  animation: lds-ellipsis2 0.6s infinite;
}
.lds-ellipsis div:nth-child(3) {
  left: 32px;
  animation: lds-ellipsis2 0.6s infinite;
}
.lds-ellipsis div:nth-child(4) {
  left: 56px;
  animation: lds-ellipsis3 0.6s infinite;
}
@keyframes lds-ellipsis1 {
  0% {
    transform: scale(0);
  }
  100% {
    transform: scale(1);
  }
}
@keyframes lds-ellipsis3 {
  0% {
    transform: scale(1);
  }
  100% {
    transform: scale(0);
  }
}
@keyframes lds-ellipsis2 {
  0% {
    transform: translate(0, 0);
  }
  100% {
    transform: translate(24px, 0);
  }
}